Forest Restoration in Campgrounds at
Kings Canyon National Park, California by
Susan B. Infalt and Truman P. Young
Intensive campground use at the Grant Grove area of Kings Canyon National Park, California, has compacted the soil and left areas without understory vegetation or tree recruitment. To better inform the restoration of these sites after closure,
we tested natural regeneration potential and planting and soil restoration methods. The tested methods included planting with container stock and direct seeding, fencing, and soil amendments of tilling, mulching, and gypsum and humus additions. Container stock had high survivorship (69-100%), while germination and survival from direct seeding was low (0.6-4.1%). Wood chip mulch was beneficial to planting woody species, but detrimental to resident herbaceous
species. Plots treated with tilling, gypsum, and humus amendments exhibited highest growth rates of container stock and greatest herbaceous species richness and cover. However, tilling without the other soil treatments reduced herbaceous cover and seedling recruitment (natural and sown). In tilled plots, gypsum treatments and humus treatments
often had neutral or detrimental effects individually, but their combination greatly increased the success of direct seeding, growth of container stock, and herbaceous cover and richness. Fencing increased volunteer tree recruitment tenfold compared to outside the plots. Some treatments in this study were beneficial to species of one morphological group but detrimental to another.
Assessing the Reintroduction Potential of the Endangered Huachuca Water Umbel in Southeastern Arizona by
Jonathan H. Titus and Priscilla J. Titus
Tiny white umbels arise on short stalks from the rhizomes of Huachuca water umbel (Lilaeopsis schaffneriana ssp. Recurva) making them difficult to detect. Photo by Priscilla Titus
The Huachuca water umbel (HWU, Lilaeopsis schaffneriana ssp. recurva) is a federally endangered aquatic perennial plant endemic to southeastern Arizona and northern Sonora, Mexico. The species was listed because of threats posed by the degradation and loss of wetlands throughout its limited range. Although the species is easily grown in a greenhouse, information regarding specific requirements that allow long-term persistence of HWU in natural habitats is lacking, and few efforts to reintroduce this species have been attempted. Using greenhouse-propagated material, we introduced 128 individual HWU plugs into four spring-fed wetland sites near Elgin, Arizona. The sites represent a range of habitat conditions.
After two years, overall survival of transplanted plugs was 60% and the area occupied had increased by 845%. This study documented the response of transplanted HWU to periodic drying, disturbance due to scouring and trampling, and sediment deposition. We also examined the number of viable seeds incorporated into a seed bank at the study location in the first season after transplanting. This case study offers a model for watershedwide reintroduction efforts of endangered plants. It also illustrates the importance of low-level disturbance and the necessity of long-term monitoring and maintenance of competing plant species in establishing viable species reintroductions.
Native Species Replace Introduced Grass Cultivars Seeded following Wildfire by
Cindy Talbott Roché, Roger L. Sheley and Robert C. Korfhage
Seeding of non-native species following wildfires to stabilize soils and prevent erosion has become a controversial practice because it risks inhibiting tree regeneration, introducing noxious weeds, and permanently replacing native species. This paper reports the fate of non-native seeded species during 31 years of postfire forest succession in northcentral Washington
state, USA. In that region, catastrophic wildfires in grand fir (Abies grandis)/pinegrass (Calamagrostis rubescens) associations characteristically result in a flush of lodgepole pine (Pinus contorta) regeneration that creates a dense tree monoculture. In the study, seven grass cultivars were broadcast seeded to prevent erosion, limit tree regeneration, and increase forage production for wildlife and livestock. Tree regeneration, native and non-native species cover, and aboveground
biomass were evaluated in 1971, 1975, 1980, 1989, and 2001. The seeded species quickly established dominant cover with levels of biomass production two to three times the level of native species. Density of tree regeneration was inversely correlated with perennial grass cover during the first 10 years. Between 1980 and 1989, the seeded grasses disappeared, long before tree canopy closure. Within 15 to 20 years native species had regained dominance, and after 30 years the last remnants of the non-native cultivars were replaced in the seeded areas by a diverse mixture of native graminoids, forbs, shrubs, and trees. In contrast, a monoculture of lodgepole pine dominated the unseeded areas. This study showed that non-native grasses seeded after wildfires do not always persist and can serve as a transition to
restoring a more diverse seral community.
Ten Years of Ecological Restoration
on a Texas Hill Country Site by
David Davidson and Patricia Davidson
We describe ten years of restoration work on a 56-ha tract of former ranchland. The historical characterization of this area at the time of the displacement of indigenous people by settlers initially formed the basis for our restoration decisions.
Today, a higher human population density and a change in climate preclude a return to the presettlement state, necessitating the formulation of other restoration goals and methods. The methods employed, metrics to determine the results of restoration, and the results of bird, butterfly, and plant surveys are listed. Changes in vegetation due to the restoration are illustrated and future plans are discussed.
Multi-Species Planting and Other Practices to Restore Forest Diversity in Northeastern Minnesota by
Robin S. Vora, Steven Lerol and Nicholas P. Danz
Forest stand diversification in terms of plant species and spacing of plantings is critical to restoring components of native forests, reducing risks of insect and disease outbreaks, and providing a variety of habitats for native birds and other forest animals. We share the results of experimentation with reforestation practices to achieve more diverse upland forests in northeastern Minnesota. We also share the results of a study to determine the impact of site preparation (rock raking) and seedling "release" (removing competing surrounding vegetation after two years) on survival and height of 19 native trees and shrubs. After five years, seedling survival across the 19 species ranged from 31% to 94%, with mean of 72%. Survival was higher for sites receiving the preparation treatment (76%) than for those not receiving the treatment (68%). Site preparation significantly increased seedling height for eight species. In year three of the study we removed nearby competing vegetation (release treatment), which resulted in significantly greater seedling height for two species and less height growth for three species after two years. We discuss the value of increases in survival and height in the context of overall forest management objectives and other management strategies to diversify forest species and structure.
The Dechannelization of Nippersink Creek: Learning about Native Illinois Streams through Restoration by Thomas B. Simpson
A collage of photos reflects efforts to restore 2.5 km of Nippersink Creek in Illinois to its original meandering course after the stream had been channelized in 1951: A backhoe closes the agricultural-era ditch channel on August 20, 2000, and McHenry County Conservation District staff and seasonal workers subsequently lay out erosion control matting along the newly recontoured banks. The aerial photo shows the newly remeandered Nippersink Creek in 2001. Photos courtesy of MCCD staff
In 1999, McHenry County Conservation District returned 2.5 km of Nippersink Creek to its original meandering course, after the stream had been channelized in 1951. The District graded the banks to an average slope of 7:1, and used coconut fiber matting and large rock to slow bank erosion. Natural Resource Management crews installed over 150,000 wetland plants along the stream edges and lower banks. Using cross-sectional elevation surveys, we followed four years of change in this newly meandered channel. In addition, we investigated the relationship of the modern stream to relict meanders scars left in the nearby stream valley. We found that, despite erosion control measures, the stream continues
to undercut its banks. Rates of lateral migration are much less than in unaltered sections of stream. Even so, bank erosion remains a problem because the modern stream is entrenched about 60 cm below the relict meanders. As the stream migrates laterally, the tall cut banks collapse into the water, reducing water quality. In response to these findings, McHenry County Conservation District installed two gravel riffles to raise the water level by approximately 60 cm over a 0.8 km reach of the stream.
Release of Roadside Native Perennial Grasses following Removal of Yellow Starthistle
Stephen L. Young and Victor P. Claassen
The ecological benefits of a roadside native perennial grass stand are compromised when invasive species become established.
We evaluated the potential to regenerate existing native perennial grass stands populated with yellow starthistle (Centaurea solstitialis) on a roadside planting in the lowland hills of the interior Coast Range of northern California. The experiment was designed to determine the effects of mowing, burning, or herbicide spraying, alone and in combination, on the vegetative cover and density of native perennial grasses and C. solstitialis. The study site contained blue wildrye (Elymus glaucus) and purple needlegrass (Nassella pulchra) as well as C. solstitialis. Burn, herbicide, and mow treatments were applied in spring 2004. After one year, C. solstitialis cover was less than 2% in all treatments that included spraying and in two years, C. solstitialis was 2% or less in all treatments except burned plots (8%) and control plots (16%). By the end of two years, percent cover and activity (i.e., growth and dormancy) of native perennial grasses were significantly greater for management treatments that included at least two of the tested vegetation control techniques. This study suggests that a combination of vegetation control techniques is necessary to nearly eliminate C. solstitialis and increase late summer cover and activity of native perennial grasses.
